Telephone with integrated hearing aid

ABSTRACT

An integrated telephone and hearing aid that has a single in-ear speaker is disclosed. The illustrative embodiments automatically adapt the operation of the hearing aid based on whether a telephone call is in progress or not. For example, when the user is not engaged in a telephone call, the illustrative embodiments function as a normal hearing aid. But when the user does become engaged in a telephone call, the illustrative embodiments alter the hearing aid function so that the user can hear the telephone call. For example, the illustrative embodiments attenuate the hearing aid function while a call is in progress so that the user can hear both the telephone call and retain some, albeit diminished, auditory input from the environment. This enables, for example, the user to still hear loud sounds (e.g., a car horn, a fire alarm, a person screaming, etc.).

FIELD OF THE INVENTION

The present invention relates to telecommunications equipment ingeneral, and, in particular, to a telephone with an integrated hearingaid.

BACKGROUND OF THE INVENTION

Telephones have become ubiquitous, and hands-free headsets that rest ina user's ear are gaining in popularity. Furthermore, with the advent ofelectronic miniaturization and wireless standards such as “Bluetooth,”entire telephones that rest in and/or on a user's ear are becomingavailable and will surely be popular.

Since such hands-free headsets typically employ an in-ear speaker—onethat fits in the external auditory meatus and/or outer ear—someindividuals with hearing loss might be prohibited from having both ahearing aid and a hands-free headset in an ear at the same time.Therefore, the need exists for a single apparatus that physicallyenables a user to have both a hearing aid and a hands-free headset in anear at the same time.

SUMMARY OF THE INVENTION

The present invention enables the integration of a telephone and ahearing aid into a single apparatus having a single in-ear speaker, and,therefore, ameliorates the problem of wearing a hearing aid and anin-ear telephone simultaneously.

The illustrative embodiments automatically adapt the operation of thehearing aid based on whether or not the user is engaged in a telephonecall. For example, when the user is not engaged in a telephone call, theillustrative embodiments function as a normal hearing aid. But when theuser does become engaged in a telephone call, the illustrativeembodiments alter the hearing aid function to enhance the use's abilityto hear the telephone call.

Furthermore, the inventors of the present invention recognize thatcompletely turning off the hearing aid while a call is in progress mightbe dangerous or disadvantageous because it diminishes the user'sawareness of his or her environment. Therefore, the illustrativeembodiments attenuate the hearing aid function while a call is inprogress so that the user can hear both the telephone call and retainsome, albeit diminished, auditory input from the environment. Thisenables, for example, the user to still hear loud sounds (e.g., a carhorn, a fire alarm, a person screaming, etc.).

In some embodiments of the present invention, the hearing aid functionis attenuated by reducing the gain of the hearing aid uniformly acrossall frequencies of the amplified acoustic signal. In contrast, someembodiments of the present invention attenuate some frequencies morethan others. For example, the incoming sound of a telephone call isbandwidth limited to a range of between f₁ and f₂ Hz. In a typicaltelephony system f₁=300 Hz and f₂=3000 Hz. Therefore, some embodimentsof the present invention reduce the gain of the hearing aid more forfrequencies between f₁ and f₂ Hz than for frequencies below f₁ or abovef₂. This also helps the user to hear both the ongoing telephone call andto be aware of his or her environment.

The first illustrative embodiment comprises: a microphone for convertinga first acoustic signal into a first electromagnetic signal s₁(t); areceiver for receiving a second electromagnetic signal s₂(t); aprocessor for generating a third electromagnetic signal s₃(t) based ona₁(t)·s₁(t) and a₂(t)·s₂(t), wherein |a₁(t₁)/a₂(t₁)| changes basedwhether the apparatus is engaged in a telephone call or not; and aspeaker for converting the third electromagnetic signal s₃(t) into asecond acoustic signal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a rendering of telephone/hearing aid 100 in accordancewith the first illustrative embodiment of the present invention.

FIG. 2 depicts a block diagram of the salient components oftelephone/hearing aid 100 in accordance with the first illustrativeembodiment of the present invention.

FIG. 3 depicts a rendering of telephone/hearing aid 200 in accordancewith the second illustrative embodiment of the present invention.

FIG. 4 depicts a block diagram of the salient components oftelephone/hearing aid 200 in accordance with the second illustrativeembodiment of the present invention.

DETAILED DESCRIPTION

FIG. 1 depicts a rendering of telephone/hearing aid 100 in accordancewith the first illustrative embodiment of the present invention. Asdepicted in FIG. 1, telephone/hearing aid 100 comprises: housing 101,microphone 102, speaker 103, and volume control 104. In accordance withthe first illustrative embodiment, telephone/hearing aid 100 is awireless telephone (e.g., a cordless telephone, a cellular telephone,etc.) that operates with the telephone system via radio rather than viaa wire. It will be clear to those skilled in the art, however, how tomake and use embodiments of the present invention in whichtelephone/hearing aid 100 is a wireline telephone.

Housing 101 is designed like a hearing aid so that it can be worn withinthe external auditory meatus and outer ear. It will be clear to thoseskilled in the art how to make and use housing 101. Microphone 102,speaker 103, and volume control 104 are all described in detail below.

FIG. 2 depicts a block diagram of the salient components oftelephone/hearing aid 100 in accordance with the first illustrativeembodiment of the present invention. As depicted in FIG. 2,telephone/hearing aid 100 comprises: microphone 102, speaker 103, volumecontrol 104, antenna 105, wireless transmitter 106, receiver 107,processor 108, and amplifier 109, interconnected as shown.

Microphone 102 picks up an acoustic signal within the vicinity ofhousing 101, converts it to an electromagnetic signal, s₁(t), and feedssignal s₁(t) to processor 108, in well-known fashion. In accordance withthe first illustrative embodiment, signal s₁(t) is a wideband signalwith a frequency band in excess of [f₁,f₂].

Receiver 107 receives an incoming electromagnetic signal (e.g., atelephone call, etc.) via antenna 105 from a remote transmitter (notshown), demodulates the incoming signal, and passes the demodulatedsignal, s₂(t), to processor 108, in well-known fashion. In accordancewith the first illustrative embodiment, signal s₂(t) represents aband-limited acoustic signal with a frequency range of [f₁,f₂].

Speaker 103 receives a third electromagnetic signal, s₃(t), fromprocessor 108 via amplifier 109 and converts it into an acoustic signal,in well-known fashion. How processor 108 generates signal s₃(t) isdescribed in detail below.

Amplifier 109 receives signal s₃(t) from processor 108 and amplifies itin well-known fashion. The gain of amplifier 109 is controlled by volumecontrol 104, which enables a user of telephone/hearing aid 100 to affectthe volume (i.e., the amount of acoustical energy) of the sound outputof speaker 103. Furthermore, the gain of amplifier 109 is not affectedby whether a telephone call is in progress or not.

Transmitter 106 receives an outgoing electromagnetic signal fromprocessor 108, modulates the outgoing signal, and transmits themodulated signal via antenna 105, in well-known fashion.

Processor 108 receives:

-   -   (1) signal s₁(t) from microphone 102, and    -   (2) signal s₂(t) from receiver 107,    -   and generates based on those signals:    -   (1) the output to transmitter 106, and    -   (2) signal s₃(t).

When there is no call in progress (i.e., s₂(t)=0), telephone/hearing aid100 functions solely as a hearing aid and, therefore, processor 108generates signal s₃(t) based solely on signal s₁(t). For example,s ₃(t)=a ₁(t)·s ₁(t)  (Eq. 1)

wherein a₁(t) is a coefficient that affects the gain or contribution ofsignal s₁(t) to signal s₃(t).

In contrast, when there is a call in progress (i.e., s₂(t)≠0)),telephone/hearing aid 100 functions both as a hearing aid and as atelecommunications device. In this case, processor 108 combines, asdescribed below, signal s₂(t) and signal s₁(t) to produce signal s₃(t).For example,s ₃(t)=a ₁(t)·s ₁(t)+a ₂(t)·s ₂(t)  (Eq. 2)

wherein a₂(t) is a coefficient that affects the relative contribution ofsignal s₂(t) to signal s₃(t).

To ensure that the total sound energy entering the user's ear is aconstant regardless of whether a telephone call is in progress or not,the total energy of signal s₃(t) is maintained at a constant level bothwhen a telephone call is in progress and when it is not. This isaccomplished by having processor 108 automatically vary the coefficientsa₁(t) and a₂(t), or the ratio of a₁(t)/a₂(t), based on whether atelephone call is in progress or not. In other words, the absolute valueof the ratio of a₁(t)/a₂(t) is less when a call is in progress than whena call is not in progress (i.e., when signal s₂(t) is less than athreshold).

Furthermore, processor 108 filters—in the frequency domain—signal s₁(t)from microphone 102 so that the frequency components in signal s₁(t) inthe frequency range [f₁,f₂] are more attenuated than the frequencycomponents below f₁ or above f₂. In particular, processor 108 generatessignal s₃(t) based on:s ₃(t)=f(a ₁(t)·[h(t)*s ₁(t)]+a ₂(t)·s ₂(t))  (Eq. 3)

wherein h(t) is the impulse response of a frequency-domain notch filterwith a notch band of [f₁,f₂]. It will be clear to those skilled in theart how to filter signal s₁(t) in this way.

Furthermore, while a call is in progress, processor 108 feeds the inputfrom microphone 102—which includes the user's voice—into transmitter 106for transmission via antenna 105 and—for the purposes of sidetone—intosignal s₃(t).

FIG. 3 depicts a rendering of telephone/hearing aid 200 in accordancewith the second illustrative embodiment of the present invention. Asdepicted in FIG. 2, telephone/hearing aid 200 comprises: housing 201,microphone 202-1, stalk 210, microphone 202-2, speaker 103, and volumecontrol 104. In accordance with the second illustrative embodiment,telephone/hearing aid 200 is a wireless telephone (e.g., a cordlesstelephone, a cellular telephone, etc.) that operates with the telephonesystem via radio rather than via a wire. It will be clear to thoseskilled in the art, however, how to make and use embodiments of thepresent invention in which telephone/hearing aid 200 is a wirelinetelephone.

Housing 201 is designed like a hearing aid so that it can be worn withinthe external auditory meatus and outer ear. It will be clear to thoseskilled in the art how to make and use housing 101.

Stalk 210 is a structural member that positions microphone 202-1 closerto a user's mouth than microphone 202-2, which enables microphone 202-1to pick up more of the user's voice during a telephone call than doesmicrophone 202-2. Although both microphones will typically pick up manycommon sounds, microphone 202-1 is designed to pick up the user's ownvoice, whereas, in contrast, microphone 202-2 is designed to pick up allsounds in the vicinity of housing 201. The purpose for having twodifferent microphones that are designed to pick up different sounds isdescribed in detail below. Microphone 202-1, microphone 202-2, speaker203, and volume control 204 are also all described in detail below.

FIG. 4 depicts a block diagram of the salient components oftelephone/hearing aid 200. As depicted in FIG. 4, telephone/hearing aid200 comprises: microphone 202-1, microphone 202-2, speaker 203, volumecontrol 204, antenna 205, wireless transmitter 206, receiver 207,processor 208, and amplifier 209, interconnected as shown.

Microphone 202-1 picks up an acoustical signal at the end of stalk 210,converts it to an electromagnetic signal, s₁(t), and feeds signal s₁(t)to processor 208, in well-known fashion. In accordance with the secondillustrative embodiment, signal s₁(t) is a signal with a frequency bandof [f₁,f₂].

Microphone 202-2 picks up an acoustic signal within the vicinity ofhousing 201, converts it to an electromagnetic signal, s₂(t), and feedssignal s₂(t) to processor 208, in well-known fashion. In accordance withthe illustrative embodiment, signal s₂(t) is a wideband signal with afrequency band in excess of [f₁,f₂].

Receiver 207 receives an incoming electromagnetic signal (e.g., atelephone call, etc.) via antenna 205 from a remote transmitter (notshown), demodulates the incoming signal, and passes the demodulatedsignal, s₃(t), to processor 208, in well-known fashion. In accordancewith the illustrative embodiment, signal s₃(t) represents a band-limitedacoustic signal with a frequency range of [f₁,f₂].

Speaker 203 receives signal s₄(t) from processor 208 via amplifier 209and converts it into an acoustic signal, in well-known fashion. Howprocessor 208 generates signal s₄(t) is described in detail below.

Amplifier 209 receives signal s₄(t) from processor 208 and amplifies itin well-known fashion. The gain of amplifier 209 is controlled by volumecontrol 204, which enables a user of telephone/hearing aid 200 to affectthe volume (i.e., the amount of acoustical energy) of the sound outputof speaker 203. Furthermore, the gain of amplifier 209 is not affectedby whether a telephone call is in progress or not.

Transmitter 206 receives an outgoing electromagnetic signal fromprocessor 208, modulates the outgoing signal, and transmits themodulated signal via antenna 205, in well-known fashion.

Processor 208 receives:

-   -   (1) signal, s₁(t), from microphone 202-1,    -   (2) signal, s₂(t), from microphone 202-2, and    -   (3) signal, s₃(t), from receiver 207,    -   and generates based on those signals:    -   (1) the output to transmitter 206, and    -   (2) signal s₄(t).

When there is no call in progress (i.e., s₃(t)=0), telephone/hearing aid200 functions solely as a hearing aid and, therefore, processor 208generates signal s₄(t) based solely on signal s₂(t). For example,s ₄(t)=a ₂(t)·s ₂(t)  (Eq. 4)

wherein a₂(t) is a coefficient that affects the gain or contribution ofsignal s₂(t) to signal s₃(t).

In contrast, when there is a call in progress (i.e., s₃(t)≠0),telephone/hearing aid 200 functions both as a hearing aid and as atelecommunications device. In this case, processor 208 combines, asdescribed below, signal s₁(t), signal s₂(t), and signal s₃(t) to producesignal s₄(t). For example,s ₄(t)=a ₁(t)·s ₁(t)+a ₂(t)·s ₂(t)+a ₃(t)·s ₃(t)  (Eq. 5)

wherein a₁(t) is a coefficient that affects the gain or contribution ofsignal s₁(t) to signal s₄(t) and wherein a₃(t) is a coefficient thataffects the gain or contribution of signal s₃(t) to signal s₄(t).

To ensure that the total sound energy entering the user's ear is aconstant regardless of whether a telephone call is in progress or not,the total energy of signal s₄(t) is maintained at a constant level bothwhen a telephone call is in progress and when it is not. This isaccomplished by having processor 208 automatically vary coefficientsa₁(t), a₂(t), and a₃(t) or the ratio of a₁(t)/a₂(t) and a₂(t)/a₃(t)based on whether a telephone call is in progress or not.

Furthermore, processor 208 filters—in the frequency domain—signal,s₂(t), from microphone 202-2 so that the frequency components in signals₂(t) in the frequency range [f₁,f₂] are more attenuated than thefrequency components below f₁ or above f₂. In particular, processor 208generates signal s₄(t) based on:s ₄(t)=a ₁(t)·s ₁(t)+a ₂(t)·[h(t)*s ₂(t)]+a ₃(t)·s ₃(t)  (Eq. 6)

wherein h(t) is the impulse response of a frequency-domain notch filterwith a notch band of [f₁,f₂]. It will be clear to those skilled in theart how to filter signal s₂(t) in this way. Furthermore, while a call isin progress, processor 208 feeds the input from microphone 202-1 (i.e.,the user's voice) into transmitter 206 for transmission via antenna 205and—for the purposes of sidetone—into signal s₄(t).

It is to be understood that the above-described embodiments are merelyillustrative of the present invention and that many variations of theabove-described embodiments can be devised by those skilled in the artwithout departing from the scope of the invention. It is thereforeintended that such variations be included within the scope of thefollowing claims and their equivalents.

1. A combination telephone and hearing aid comprising: a first microphone for converting a first acoustic signal into a first electromagnetic signal; a second microphone for converting a second ambient acoustic signal into a second electromagnetic signal; a receiver for receiving a third electromagnetic signal that represents a third acoustic signal; and a speaker for converting a fourth electromagnetic signal into a fourth acoustic signal, wherein said fourth electromagnetic signal is based on said first electromagnetic signal, said second electromagnetic signal, and said third electromagnetic signal.
 2. The combination telephone and hearing aid of claim 1 further comprising a transmitter for transmitting said first electromagnetic signal.
 3. The combination telephone and hearing aid of claim 1 wherein the relative contribution of said first electromagnetic signal, said second electromagnetic signal, and said third electromagnetic signal to said fourth electromagnetic signal is based on whether said combination telephone and hearing aid is engaged in a call. 